Apparatus for the control of highway-crossing signals



Oct; 23, 1928. 1,688,912

l -l. s. YOUNG ET AL APPARATUS FOR THE CONTROL OF HIGHWAY CROSSING- SIGNALS Filed Oct. 7, 1926 INVENTOR S 1 Patented Oct. 23, 1928.

UNITED STATES PATENT OFFICE.

HENRY S. YOUNG, OF VJILKINSBURG, AND ROBERT M. GILSQN, OF PET'ESBUR-GH, PENNSYLVANIA, ASSIGNORS TO THE UNIONSWITCH & SIGNAL COMPANY, OF SWISSVALE, PENNSYLVANIA, A. CORPORATION OF PENNSYLVANIA.

APPARATUS FOR THE CONTROL OF HIGHWAY-CROSSING SIGNALS.

Application filed October 7, 1926.

Our invention relates to apparatus for the control of highway crossing signals, and particularly to apparatus suitable. for use in territory provided with train controlling means of what is known as the coded type, that is,

the type wherein current is periodically supplied to the track rails for the control of train carried governing mechanism.

lVe will describe two forms of apparatus embodying our invention, and will then point out the novel features thereof in claims.

In the accompanying drawing, Fig. 1 is a diagrammatic view showing one form of apparatus embodying our invention. Fig. 2 a

diagran'nnatic view showing a modification of a portion of the apparatus shown in Fig. 1 and also embodying our invention.

Similar reference characters refer to similar parts in each of the views.

Referring first to Fig. 1, the reference characters l and l designate the track rails of a railway over which traffic normally moves in the direction indi ated by the arrow, but over which trallic may at times move in the opposite direction. These rails are divided by insulated joints 2 to form two track sections .-l5 and BC, and a highway Q, intersects the railway track at substantially the junction point B of these sections. A highway crossing signal S is located at the intersection of the railway and the highway, and this signal in the form here shown is of the electric bell type.

Section A-B is provided with a track circuit comprising a transformer H the secondary of which is connected across the rails adjacent the point B, and a track relay L connected across the rails adjacent the point A. The primary of transformer H is supplied with alternating signaling current from the secondary of a transformer T, the primary of which is constantly connected with a source of current not shown in the drawin Interposed between transformers T and H is a normally closed contact 15 of a codlng device R having a controlling circuit which passes from terminal 3 of a suitable source of current through back contact 5 of track relay L back contact 14f of coding device R the winding of coding device R and a front contact 10 of a relay E, to terminal 4 of the same source of current. Assuming that relay E is energized, coding device R will be (lo-energized when track section AB is un- Serial No. 140,010.

occupied, so that signaling current will then be supplied continuously to the rails of this section. When a train enters section A-B, however, the circuit for the coding device R will be closed at contact 5, whereupon this codmg device will operate to periodically interrupt the supply of signaling current to the rails of section A.B. This periodically interrupted signaling current constitutes what I will term train control current.

Section B-O is provided with a track circuit comprising a transformer K the secondary of which is connected with the rails adj acent the point B, and a track relay L having two windings 22 and 23. finding 22 is connected across the rails adjacent point C, and

winding 23 is constantly supplied with alter hating signaling current from terminals 3 and i of a suitable source of such current. A resistance 24 is interposed between winding 22 and one of the track rails 1. Relay L controls a coding device it, the circuit including back contact 19 of relay L and back contact 16 of the coding device, so that this coding device is at rest when section 13-0 is unoccupied and in operation when the section is occupied. When the coding device R is at rest resistance 24 is shunted by back contact 18 of the coding device, whereas when the coding device is in operation this shunt is periodically opened and at thesame time alternating current is periodically supplied to the primary of a transformer U from the secondary of a transformer M, through front contact 17 of the coding device B The se ondary of transformer U is connected across the rails of section BC adjacent the point C, and the primary of transformer l\L is connected with the same source as that which supplies current to the primary of transformer T. The purpose of the resistance 24 is to prevent over-energization of winding 22 of relay L by the periodically interrupted current which is supplied to transformer U when relay L is de-energized.

The reference character D designates a quick-acting relay which receives energy from the rails of section A-B at an intermediate point in the section, a transformer N preferably being interposed between. this relay and the track rails. The reference character E design ates arelay having two windings 20 and 21. Winding 20 receives energy from the rails of section BC at an intermediate point in this section through the medium of a transformer P, and winding 21 is Constantly connected with the alternating current terminals 3 and 4. Relay D is connected with the rails at substantially the point at which it is desired that the crossing bell S should start to operate when a train is moving in the direction indicated by the arrow, and relay E is connected with the rails of section BC substantially at the point at which it is desired that the bell should start to operate when a train is moving in theopposite direction. 7

Relays D and E control a slow-releasing relay F, and the relays D, E and F control an interlocking relay G which in turn controls the bell S. The relay Gcomprises two magnets G and G The circuit for the slow-releasing relay 1* is from terminal 3, through front contact 6 of relay D, front contact 8 of relay E, and the winding of relay F to terminal 4. Magnet G is provided with a first circuit which passes from terminal3 through front contact 11 of relay F and the winding of magnet G to terminal 4. This magnet is provided with a second circuit which passes from terminal 3, through front contact 6 of relay D, back contact .8 of relay E and the winding of magnet G toterminal 4. Magnet G is provided.

with a thirdcircuit which passes from terminal-3, t-hrough front contact 12 controlled by magnet G front contact 7 of relay D, and the winding of relay G to terminal 4. Magnet Gr has only one circuit, and this circuit is controlledby front contact 9 of relay E. The crossing bell S is controlled in the usual manner contacts12 and13 ofinterlocking rela lhe operation of the'apparatus shown in Fig. 1, is as follows: When the two'sections .are unoccupied all relays are energized, so .that the parts are in the conditions shown in the drawing. When a train moving in the direction indicated by the arrow enters section At -B, it de-energizes track relay L thereby causing the coding device R to-operate whereupon alternatingcurrentis periodically-supplied tothe rails of this section. RelayD will release during the intervalsbetween the impulses of this current, but relay F will remain closed because ofits s1owacting characteristic, and, consequently, magnet G of the interlocking relay will remain energized because of the first circuit traced hereinbefore for this magnet. When the train approaches the point .at which transformer N isconnected with the track rails,

relay D will remain open, whereupon relay F will release. All ofthe circuits for magnet G are then open sothat this magnet will of the coding device R so that periodically interrupted alternating current will be supplied to the rails at point C by transformer The connection of transformer U with the track rails is the reverse of the connection of transformer K with the track rails, so that relay E is not energized to close its front contacts by the current supplied to the rails from transformer U. Relay E accordingly becomes deenergized when the train enters section .B-C. When the rear end of the train leaves section AB, relay D be comes-energized and remains continuously energized because the operation of the coding device R is prevented due to the fact that the circuit for this coding device is open at front contact 10 of relay E. The second circuit for magnet G is now closed at front contact 6 of relay D and backs'contact 8 of relay E,'so that contact 12 opens and stops the operation of the bell S. Magnet G is, of course, de-energized because contact 9 is open, but as is well understood, contact 13 will not close because contact 12 was closed. at the time that magnet G became de-energized. After the train passes the point of connection of transformer P with the track rails, relay E will again become energized so that magnet G will become energized, and the closing of front contact 8 of relay E will again en ergize relay F, so that the parts of the apparatus associated with the crossing bell S are restored to their normal conditions. When the train leaves section B-C, track relay L will become energized and so will stop the operation of the coding device R We will now assume that a train moving in the direction opposite to that indicated by the arrowenters section BC. As this train approaches the point of connection of transformer P with the track rails, it will deenergize relay E and this in turn will de-energize magnet G and so will start the bell S in operation. The-opening of front contact 8 of relayIE de-energizes relay Fso that this relayisrendered ineffective to control the interlocliing relay G during a train movement in the direction now under consideration. Magnet G remains energized due to its third circuitincluding its own front contact 12 and contact 'T of relay D. Whentheiforward end of the train enters section A--B, it deenergizes relay D, which in turn de-energizes magnet G so that when the rear end of the train leaves section B.C the bell S stops I ringing. WVhen the train leaves section A 'B, relays D and F will again become energized-so that the parts of-the apparatus will be restored to their normal conditions.

The circuits for magnet G of the interlocking relay G are such as to insure proper 0perationo'f this relay for all train movements including a light engine moving at high speed in the direction opposite to that indicated by the arrow. Furthermore, it will be noted that relay F is de-energized before such a train reaches point B, so that the slow-releasing characteristic of this relay will not interfere with the proper operation of the interlocking relay G.

Referring now to Fig. 2, the apparatus here shown is suitable for use on an electrified railway wherein the signaling current is of one frequency, such as 60 cycles, and the train controlling current is of another frequency, such as 100 cycles. The signaling current is supplied to section BC by a transformer K and the second winding 23 of the track relay E is normally supplied with 60 cycle current from a transformer V through back contact 25 of the coding device R The train controlling current is supplied to the rails at the point C by a transformer W, the secondary of which is interposed between winding 22 of rel ay L and the track rail 1. When the coding device R is at rent, the primary of transformer iV is placed on short circuit by contact 17, so that this r sformer offers substantially no impedance to the flow of 60 cycle current from transformer K to relay winding 22. hen the coding device R is in operation, however, 100 cycle current is periodically supplied to the primary of transformer from a transformer V through the front point of contact 17, and while this current is being supplied to transformer V, the supply of cycle current to the relay winding 23 is discontinued at contact 25. It follows that when a train leaves section BC, relay winding 22 will be constantly supplied with cycle current and intermittently supplied with 100 cycle current, but that while the 100 cycle current is being supplied the supply of 60 cycle current will be discontinued in winding 23, so that this relay will become energized even if it is a relay of the centrifugal type.

Although we have herein shown and clescribed only two forms of apparatus embodying our invention, it is understood that various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of our invention.

Having thus described our invention, what we claim is:

1. In combination, a railway track divided into two successive sections A-B and B-C, a highway intersecting said track at substantially the junction point of said sections, means for supplying periodically interrupted alternating train controlling current to the rails of section AB adjacent point B and to the rails of section BC adjacent point C, asource of alternating signaling current connected with the rails of section B C adjacent point B and the relative polarity of which is the reverse of that of said train con trolling current supplied at point C, a quick acting relay D receiving energy from the rails at an intermediate point in section A.-B, a relay E having a winding receiving energy from the rails at an intermediate point in section BC and responsive to the relative polarity oi said signaling current but not to that of said train controlling current, a slow acting relay F having a circuit includ ing front contacts of relays D and E in series, an interlocking relay having two magnets G and G", a first circuit for magnet (a controlled by a front contact of relay E, a second circuit for magnet G including a front contact of relay D and a back contact of relay E, a third circuit for magnet G ineluding a front contact of relay D and a contact close l when the armature tor magnet G is closed, a circuit for magnet G controlled by a front contact of relay E, and a highway crossing signal controlled by said interlocking relay.

2. in combination, a railway track divided into two successive sections i k-B and B(), a highway intersecting said track at substantially the junction point of said sections, means for supplying periodically interrupted alternating train controlling current to the rails of section Al3 adjacent point B, and to the rails of section l5-C adjacent point C, a source of alternating signaling current con nected with the rails of section B@ adjacent point B and the relative polarity of which is the reverse of that of said train controlling current supplied at point C, a quick acting relay D receiving energy from the rails at an intermediate point in section A-B, a relay E having a winding receiving energy from the rails at an intermediate point in section B@ and responsive to the relative polarity of said signaling current but not to that of said train controlling current, a slow acting relay controlled by said relays D and E, and a highway crossing signal controlled by said relays D and E by said slow acting relay.

3, In combination, a railway track divided into two successive sections AB and 13-0, at highway intersecting said track at substantially the junction point of said sec tions, means for supplying periodically interrupted alternating train controlling current to the rails of section AB adjacent point B, and to the rails of section B-@ adjacent point C, a source of alternating signaling current connected with the rails of section BC adjacent point B and the relative polarity of which is the reverse of that of said train controlling current supplied at point C, a quick acting relay D receiving energy from the rails at an intermediate point in section AB, a relay E having a winding receiving energy from the rails at an intermediate point in section BC and responsive to the relative polarity of said signaling current but not to that of said train controlling ill?) lit! current, and a highway crossing signal controlled by said relays D and E.

4. In combination, a railway track divided into two successive sections AB and BC, a highway intersecting said track at substan tially the junction point of said sections, means for supplying periodically interrupted alternating train controlling current to the rails of section A-B adjacent point B, a source of signaling current connected with the rails of section B-C adjacent point B, two relays D and E receiving energy from the rails of sections A-B and 13-0 respectively, a slow acting relay F having a circuit including front contacts of relays D and E in series, an interlocking relay having two magnets G and G a first circuit for magnet G controlled by a front contact of relay F, a second circuit for magnet G including a front contact of relay D and a back contact of relay E, a third circuit for magnet G including a front contact of relay D and a contact closed when the armature for magnet G is closed, a circuit for magnet Gr controlled by a front contact of relay E and a highway crossing signal controlled by said interlocking relay.

5. In combination, a railway track divided into two successive sections A-B and B--C, a highway intersecting said track at substantially the junction point of said sections, means for supplying periodically interrupted alternating train controlling current to the rails of section AB adjacent point B, a source of signaling current connected with the rails of section BG adjacent point B, two relays D and E receiving energy from the rails of sections AB and 13-0 respectively, a slow acting relay controlled by said relays D and E, and a highway crossing signal controlled by said relays D and E and by said slow acting relay.

6. In combination, a railway track divided into two successive sections A-B and BC, a highway intersecting said track at substantially the junction point of said sections,

with the rails at one end of said section, a

track relay connected with the rails at the other end of said section, means including a coding device for at times applying periodically interrupted alternating train control current to the rails at the relay end of said section, a resistance interposed between said relay and one of the rails of said section, and means controlled by said coding device for closing a shunt around said resistance when train control current is not being supplied to the rails and for opening said shunt when train control current is being supplied to the rails.

In testimony whereof We aflix our signatures.

HENRY s. YOUNG. ROBERT M. GILSON. 

